Webb is 9-3 in 15 lifetime starts against Los Angeles, though he picked up a no-decision in the July 20 meeting after allowing six hits and a run over eight innings of Arizona's 6-5 loss in Phoenix.
He is 3-0 in six starts since his last loss, which came June 22 at Minnesota. Overall, he is 14-4 with a 3.14 ERA on the season. However, he's 8-3 in 13 road starts with a 2.59 earned run average in 83 1/3 innings.
For Los Angeles, veteran righty Derek Lowe faces Webb and the Diamondbacks again while looking for a fourth straight victory.
The 35-year-old Michigan native is 3-0 in four starts since June 29, with the no-decision coming after he tossed 5 1/3 innings of seven-hit, four-run ball against Arizona on July 20.
He bounced back with a 6-0 masterpiece against Washington six days later, allowing just one hit in eight scoreless innings while walking one and striking out four. Lifetime against the Diamondbacks, Lowe is 4-6 in 14 starts with a 4.44 ERA in 73 innings.